400123100 has 72 divisors (see below), whose sum is σ = 957990768. Its totient is φ = 144115200.

The previous prime is 400123093. The next prime is 400123103. The reversal of 400123100 is 1321004.

It is a happy number.

It is a super-2 number, since 2×400123100² = 320196990307220000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400123103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 49547 + ... + 57053.

Almost surely, 2^400123100 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400123100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (478995384).

400123100 is an abundant number, since it is smaller than the sum of its proper divisors (557867668).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

400123100 is a wasteful number, since it uses less digits than its factorization.

400123100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7575 (or 7568 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 400123100 is about 20003.0772632613. The cubic root of 400123100 is about 736.8818760220.

Adding to 400123100 its reverse (1321004), we get a palindrome (401444104).

The spelling of 400123100 in words is "four hundred million, one hundred twenty-three thousand, one hundred".